Air-conditioning apparatus for vehicle use

Abstract

An air-conditioning apparatus for vehicle use which can obtain sufficient heater capacity even in a cold-climate region, can utilize an existing heater unit, can combine a combustion type heater with a simple assembly operation, and can utilize exhaust heat of a motor for travel use of an automobile for heating a passenger compartment. The air-conditioning apparatus includes a refrigeration cycle connecting a refrigerant compressor, a refrigerant/water heat exchanger, a first pressure-reducer, and an exterior heat exchanger in an annular configuration. Further, a hot-water cycle connects the refrigerant/water heat exchanger, a hot-water heater core, an exhaust-heat cooler, and a water pump in an annular configuration and connects a combustion type heater in parallel with the refrigerant/water heat exchanger. Accordingly, during heat-pump hot-water heating, hot water, with a temperature raised by refrigerant condensation by the refrigerant/water heat exchanger, circulates in the hot-water heater core so as to obtain a required heater capacity. During combustion heater hot-water heating, hot water, with a temperature raised by combustion fuel in the combustion type heater, circulates in the hot-water heater core so as to obtain sufficient heating capacity even in a cold-climate region.

What is claimed is: 
     
       1. An air-conditioning apparatus for use in a vehicle having a passenger compartment, said air-conditioning apparatus comprising: a duct for leading air toward said passenger compartment;   a blower for moving air within said duct to said passenger compartment;   a refrigeration cycle including a refrigerant compressor for compressing and discharging refrigerant, a refrigerant/water heat exchanger for exchanging heat between refrigerant discharged from said refrigerant compressor and hot water in order to heat said hot water, and a refrigerant evaporator for cooling air by means of refrigerant evaporation heat; and   a hot-water cycle including a pump for circulating said hot water heated by said refrigerant/water heat exchanger, and a hot-water type heater disposed within said duct for heating air flowing within said duct by means of hot water entering said hot-water type heater from said refrigerant/water heat exchanger.   
     
     
       2. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said refrigeration cycle includes an exterior heat exchanger disposed outside said air duct and connected in series with and on a downstream side of said refrigerant compressor as determined by a direction of refrigerant flow from said refrigeration compressor. 
     
     
       3. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said hot-water cycle includes a radiator for exchanging heat between air outside said passenger compartment and said hot water to cool said hot water connected in series with an exhaust-heat cooler for cooling, by means of hot water, vehicle-mounted electrical devices which generate heat when electrically charged. 
     
     
       4. An air-conditioning apparatus for use in a vehicle according to claim 3, wherein said vehicle-mounted electrical devices include a motor used when said vehicle travels and an inverter also used when said vehicle travels, said inverter including transistors that generate heat when electrically charged. 
     
     
       5. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said hot-water cycle includes a combustion type heater for heating hot water via combustion of fuel connected in series with said hot-water type heater. 
     
     
       6. An air-conditioning apparatus for use in a vehicle according to claim 2, further comprising a pressure-reducing means connected between said refrigerant/water heat exchanger and said exterior heat exchanger. 
     
     
       7. An air-conditioning apparatus for use in a vehicle according to claim 1 wherein said hot-water cycle includes an exhaust-heat cooler for cooling via hot water, vehicle-mounted electrical devices, which generate heat when electrically charged, connected in series with said hot-water type heat exchanger. 
     
     
       8. An air-conditioning apparatus for use in a vehicle according to claim 7, wherein said vehicle-mounted electrical devices include a motor used when said vehicle travels and an inverter also used when said vehicle travels, said inverter including transistors that generate heat when electrically charged. 
     
     
       9. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said hot-water cycle includes an electrical hot-water heater for heating hot water using an electrical heater connected in series with said hot-water type heater. 
     
     
       10. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said refrigeration cycle positions said refrigerant evaporator on an upwind side of said hot-water type heater within said duct. 
     
     
       11. An air-conditioning apparatus for use in a vehicle according to claim 1, further comprising a rotational speed control means for controlling rotational speed of said refrigerant compressor in order to perform capacity control. 
     
     
       12. An air-conditioning apparatus for use in a vehicle according to claim 3, wherein said hot-water cycle further includes a bypass passage for allowing hot water to bypass said radiator. 
     
     
       13. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said hot-water type heater includes an air-mix damper for changing the amount of air heated in said duct. 
     
     
       14. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said refrigeration cycle includes an exterior heat exchanger disposed outside said duct and connected in series with and on a downstream side of said refrigeration compressor as determined by a direction of refrigerant flow from said refrigeration compressor, and a pressure-reducing means connected between said refrigerant/water heat exchanger and said exterior heat exchanger; wherein said hot-water cycle includes a combustion type heater for heating hot water via combustion of fuel connected in series with said hot-water type heater; and   wherein said air-conditioning apparatus includes a heat-pump hot-water heater and a combustion-heater hot-water heater as said combustion type heater, and said heat-pump hot-water heater and said combustion-heater hot water heater are selectively utilized based on a temperature of air outside said passenger compartment.   
     
     
       15. An air-conditioning apparatus for use in a vehicle according to claim 1, further comprising a water-cooled type internal combustion engine having a water-cooling portion within which water circulates; and an electrical generator driven by rotation of said water-cooled type internal combustion engine;   wherein said refrigerant compressor is an electromotive type refrigerant compressor which receives a supply of electrical power from said electrical generator in order to operate; and   wherein said hot-water cycle includes said water-cooling portion connected in series with and on a downstream side of said refrigerant/water heat exchanger as determined by a direction of water flow from said refrigerant/water heat exchanger.   
     
     
       16. An air-conditioning apparatus for use in a vehicle according to claim 1, further comprising a water-cooled type internal combustion engine having a water-cooling portion within which water circulates; wherein said refrigerant compressor is driven by rotation of said water-cooled type internal combustion engine; and   wherein said hot-water cycle includes said water-cooling portion connected in series with and on a downstream side of said refrigerant/water heat exchanger as determined by a direction of water flow from said refrigerant/water heat exchanger.   
     
     
       17. An air-conditioning apparatus for use in a vehicle according to claim 1, further comprising an inverter acting a drive power supply; wherein said refrigerant compressor is an electromotive type refrigerant compressor controlled by said inverter; and   wherein said hot-water cycle includes an exhaust-heat cooler for cooling said inverter via hot water connected in series with said hot-water type heater.   
     
     
       18. An air-conditioning apparatus for use in a vehicle according to claim 1, further comprising an integral casing housing at least said refrigerant compressor and said refrigerant/water heat exchanger. 
     
     
       19. An air-conditioning apparatus for use in a vehicle according to claim 5, wherein said combustion type heater is connected in series with and on a downstream side said refrigerant/water heat exchanger as determined by a direction of hot-water flow from said refrigerant/water heat exchanger; wherein said combustion type heat exchanger is connected in series with and on an upstream side of said hot-water type heater as determined by a direction of hot-water flow from said hot-water type heater; and   wherein said combustion type heat exchanger is operated simultaneously with said refrigerant compressor.   
     
     
       20. An air-conditioning apparatus for use in a vehicle according to claim 2, wherein said exterior heat exchanger functions as a condenser for condensing refrigerant during cooler operation and functions as an evaporator for evaporating refrigerant during heater operation; and wherein refrigerant flows in a first direction in said exterior heat exchanger during cooler operation and in a second direction opposite said first direction during heater operation.   
     
     
       21. An air-conditioning apparatus for use in a vehicle according to claim 1, wherein said vehicle is an electric vehicle. 
     
     
       22. An air-conditioning apparatus for use in a vehicle having a passenger compartment, said air-conditioning apparatus comprising: a duct for leading air toward said passenger compartment;   a blower for moving air within said duct to said passenger compartment;   a first refrigeration cycle including a refrigerant compressor for compressing and discharging a first refrigerant, a heat exchanger for exchanging heat between said first refrigerant discharged from said refrigerant compressor and a second refrigerant in order to heat said first refrigerant water, and a refrigerant evaporator for cooling air by means of refrigerant evaporation heat; and   a second refrigeration cycle including a pump for circulating said second refrigerant heated by said heat exchanger, and a heater disposed within said duct for heating air flowing within said duct by means of said second refrigerant entering said heater from said heat exchanger;   wherein said heat exchanger is disposed at a downstream of said compressor to lead said first refrigerant discharged from said compressor and elevated to a high degree thereinto, and disposed at a upstream of said heater to lead said second refrigerant which has a lower degree and is heat exchanged with said first refrigerant.   
     
     
       23. An air-conditioning apparatus for use in a vehicle according to claim 22, wherein said first and second refrigerants are freon gas and hot-water, respectively.